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with great rapidity, they are always found in large numbers, and 

 consequently trees are attacked in many of their roots at the same time. 

 There is some uncertainty as to whether the same worm attacks different 

 plants, or if each one has its own special insect. When land becomes 

 infested with these worms it is not an easy matter to destroy them, as 

 they spread rapidly, and are very tenacious of life. In fact, some species 

 can remain dormant for years, and then resume activity. Leaf, bark or 

 fruit-destroying pests that can be seen and got at are comparatively easy 

 to deal with ; but these Nematode worms may be classed as dangerous 

 enemies that are difficult to destroy. When trees are affected it will 

 be advisable to uproot them at once, as there is no known cure. In 

 this way it may be possible to destroy the worms if they are 

 merely local. But when the insects are spread through a large 

 area, to destroy them is a difficult matter. Possibly the most 

 effective way of coping with the evil is to keep affected land free 

 from vegetation for a time, so that through lack of sustenance the 

 insects will die out. This cannot be done without the destruction of the 

 trees or other plants, but even this heroic remedy is necessary, or 

 otherwise the worms may spread over large areas. Various chemicals 

 in solution have been recommended, but they are somewhat uncertain 

 in their action, and are open to the objection that they may poison the 

 soil as well as the worms. Possibly some effective means of destruction 

 may be discovered and it will be well if such is the case, as the evil is 

 serious, though not generally known. Without doubt many trees die 

 from the attacks of these Nematode worms in what appears often a 

 mysterious way, and the true cause unsuspected. 



VARIOUS FORMS OF FRUIT TREE ROOT GALLS. 



Grape. 



Root Hot. This disease, which often causes serious trouble, is most 

 commonly caused by fungi, though sometimes it is due to insects. 



